Files
mayan-edms/mayan/apps/ocr/tasks.py

66 lines
2.4 KiB
Python

from __future__ import unicode_literals
import logging
import sys
import traceback
from django.conf import settings
from documents.models import DocumentVersion
from lock_manager import Lock, LockError
from mayan.celery import app
from .runtime import ocr_backend_class
from .literals import LOCK_EXPIRE
from .models import DocumentVersionOCRError
from .signals import post_document_version_ocr
logger = logging.getLogger(__name__)
@app.task(bind=True, ignore_result=True)
def task_do_ocr(self, document_version_pk):
lock_id = 'task_do_ocr_doc_version-%d' % document_version_pk
try:
logger.debug('trying to acquire lock: %s', lock_id)
# Acquire lock to avoid doing OCR on the same document version more than
# once concurrently
lock = Lock.acquire_lock(lock_id, LOCK_EXPIRE)
logger.debug('acquired lock: %s', lock_id)
document_version = None
try:
document_version = DocumentVersion.objects.get(pk=document_version_pk)
logger.info('Starting document OCR for document version: %s', document_version)
backend = ocr_backend_class()
backend.process_document_version(document_version)
except Exception as exception:
logger.error('OCR error for document version: %s; %s', document_version, exception)
if document_version:
entry, created = DocumentVersionOCRError.objects.get_or_create(document_version=document_version)
if settings.DEBUG:
result = []
type, value, tb = sys.exc_info()
result.append('%s: %s' % (type.__name__, value))
result.extend(traceback.format_tb(tb))
entry.result = '\n'.join(result)
else:
entry.result = exception
entry.save()
else:
logger.info('OCR complete for document version: %s', document_version)
try:
entry = DocumentVersionOCRError.objects.get(document_version=document_version)
except DocumentVersionOCRError.DoesNotExist:
pass
else:
entry.delete()
post_document_version_ocr.send(sender=self, instance=document_version)
finally:
lock.release()
except LockError:
logger.debug('unable to obtain lock: %s' % lock_id)
pass